The present invention generally refers to material transportation, and more specifically to a loading car for bulk material useful for incorporation in a freight train of a series of successively arranged like loading cars. In particular, the present invention refers to a loading car of a type having a box which is open on top and mounted to a frame for storing bulk material, an endless bottom conveyor positioned in a lower portion of the box in a longitudinal direction of the car and having two conveyor ends spaced from one another in the longitudinal direction, and a transfer conveyor extending at an angle to the bottom conveyor and projecting beyond the frame.
U.S. Pat. No. 4,576,538 discloses a loading car of this type which when coupled together with other like loading cars to form a freight train provides a continuous conveyance path along the length of the train so that bulk material can be dumped into the box at one end and transported to the opposite end. The drive for the bottom conveyor, typically a conveyor band, can be operated at variable speed so that a slow conveying speed results in a slow advance of bulk material enabling the box car to be fully charged. A higher conveying speed, on the other hand, allows a transport of bulk material to the preceding box car without intermediate storage. This type of loading train permits a transport of e.g. waste material generated by a cleaning machine from the adjacent end of the loading train via the respective bottom and transfer conveyors, typically also conveyor bands, to the leading box car for storage. The projecting transfer conveyor is swingable about a vertical axis so as to allow unloading of all box cars at the same time.
British Pat. No. GB 2,277,725 also describes a loading car of this type in which the transfer conveyor is swingably mounted in an area of its lower conveyor end in order to allow the transfer conveyor to be vertically adjustable by a drive from a first upper end position effecting a transfer of bulk material to the successive loading car into a second lower end position for discharge of stored bulk material directly onto the track at smaller height of drop.
U.S. Pat. No. 5,151,002 discloses a loading car which includes two parallel bottom conveyors positioned side-by-side and two parallel transfer conveyors in side-by-side disposition, with the bottom and transfer conveyors so positioned that the conveyor end of a bottom conveyor is either disposed below or above the conveyor end of the transfer conveyor so that a continuous conveyance path is provided with the conveyor ends of the transfer conveyor alternatingly disposed beneath and above the facing conveyor ends of successive bottom conveyors. Both bottom conveyors are separated from one another by a central, longitudinally extending partition, with each bottom conveyor being associated to a separate box. Although this dual arrangement of two conveyor arrangements allows parallel storage and/or transport of bulk material in two opposite conveying directions, each conveyor arrangement can be operated only in one conveying direction.